The present invention relates to an improvement in the auger type posthole digger. More specifically, an improvement in the manner in which a portable posthole digger is employed in the digging of holes in the earth for the placement of such things as fence posts, mailbox poles, deck posts, playground equipment and sign posts.
In the past, people who frequently had the need to excavate relatively narrow and deep cylindrical holes in the earth for the anchoring of posts, such as ranchers and construction companies, mainly used one of three available means to do so. The first of these was a hand held gasoline powered auger type device. The major problem with this method is that it is dangerous, often wrenching out of the operator's control when encountering varying soil conditions, consistencies and rocks. The hand held digger generally requires at least two people to operate effectively. Additionally, the amount of force required to drive the posthole digger far enough into the earth to create a hole of sufficient depth is very difficult to apply to such a device.
The second option available was a post hole digger that is mounted on its own independently powered and transportable trailer-type device. These types of devices are illustrated in U.S. Pat. Nos., 5,396,967 (Stewart) and 3,976,147 (Cunningham). While these devices provide stability and are operable by a single user, the expense of such devices can be prohibitive to small companies and individuals to own and operate. They are also quite cumbersome and difficult to move from one drilling location to another. Additionally, they may still require the user to apply manual down force to drive the auger into the earth.
A third type of posthole digger has been the attachment-type digger as illustrated by U.S. Pat. No., 3,789,931 (Quinn). This type of device is typically attached to the front loader portion of a tractor or skid steer loader. Loader tractors and skid steers (hereinafter referred to as loader tractors or loader type tractors in general) are typically used by ranchers and construction companies and thus, make an ideal power source for operating a posthole digger. The problem has been that until this time posthole diggers for loaders have required a large amount of mounting hardware in order to allow the posthole digger to properly move side to side and fore and aft. Thus, these posthole diggers have required substantial time and effort to convert the loader between a posthole digger and useable loader tractor. Further, posthole diggers of this type may only work with specific loader type attachments due to certain mounting requirements.
From the foregoing discussion, it can be seen that it would be highly desirable to provide a method of digging postholes that is easily used by one person, that is stable and safe in its use, and is inexpensive. Further, it is desirable to provide such equipment that can be used in conjunction with existing loader type equipment capable of applying the down force necessary to drive the posthole digger to a sufficient depth into the earth. Finally, it can be seen that it would be desirable to provide such a method that could be easily engaged to and disengaged from equipment already existing in the user's inventory.